I've conducted a short Q & A session with Chris Rubyor, Westwood's Ra2/YR Community manager:
Rob: We haven't heard much news on the second Yuri's Revenge patch.. could you give us some information on what's being worked on and any ETA? Delphi: Nothing is currently planned, but we'll keep ever posted if this changes.
Rob: Are there likely to be any more official map packs released soon? Delphi: Yes, we plan to release a new map pack once a month for the next six months.
Rob: Are there any Yuri's Revenge events (e.g. WW Vs. The World/Developers Chat) planned for the near future? Delphi: We'll continue to update the website with news on a daily basis with tons of goodies.
Rob: Is there any possibility of a second expansion pack for Red Alert 2? Delphi: Nothing is planned at this time.
Well, some interesting answers, make of them what you will!